Electrodeposition device

ABSTRACT

The invention relates to an electrodeposition device, having two or more emission electrodes that can be connected to a common electrical supply line and an electrically insulating electrode holder, wherein the electrode holder is made of plastic and receives the electrodes, the electrical connections thereof and a contact surface for the connection to the electrical supply line.

BACKGROUND OF THE INVENTION

The present invention relates to an electrodeposition device.

Such a device is known from DE 197 01 463 C1.

The invention is based on the problem of supporting the most economicalproduction, reliable functioning, and space-saving design of thedeposition device.

SUMMARY OF THE INVENTION

In other words, the invention proposes to use a plastic component,instead of the traditional ceramic insulation used in the high-voltagedomain, and this holds the electrodes themselves, as well as the contactsurface by which the electrodes can be connected to an electrical feedline, and the electrical connection lines between the contact surfaceand the electrodes are also arranged inside this plastic component.

Thanks to the use of plastic as the insulator, an outstanding resistanceto vibrations is achieved. Furthermore, the plastic component with itsvibration-damping properties can lengthen the lifetime of theelectrodes, which might be sensitive to vibrations. The plasticcomponent can be made by injection molding, and the other components canbe cast in this plastic. Thus, on the one hand, rational production ofthe overall component is made possible, in particular production thatnot require costly mounting of electrodes, of contact surfaces, and ofthe electrical connection lines lying between them, and on the otherhand an especially space-saving design of the subassembly is possible,since the injection molding around them allows a more space-savingdesign than if they were mounted on the electrode holder.

To special advantage, these components can also be designed as a singleunit, for example, in injection molding or diecasting. In this case, theelectrodes are joined together to form a one-piece unit, which moreoveralso constitutes the contact surface where the electrical feed line canbe connected.

In particular, the electrodes can consist of plastic. When theseelectrodes are embedded in the plastic component referred to at theoutset, an optimally low-voltage behavior of the subassembly as a wholeresults by virtue of similar material properties (e.g., coefficient ofthermal expansion), so that its functional safety and freedom frommalfunctions is further improved. Surprisingly, it is possible to makethe electrodes from plastic, for even though the mode of functioning ofthe electrodeposition device is based on the electrical conductance ofthe electrodes, and even plastics that can be rendered conductive have acomparatively high resistance as compared to metallic materials, whichis generally considered as unfavorable, nevertheless this relativelyhigher resistance of plastic electrodes plays no functionally relevantrole, because of the low currents, so that good separating performancecan also be achieved with such electrodes made of plastic.

In particular, if the electrodes, their connection lines, and thecontact surface are configured as a generally one-part workpiece, anespecially economical production of this workpiece by plastic injectionmolding is possible, so that the electrodeposition device is especiallywell designed both in terms of its manufacturing costs and its operatingbehavior.

A sample embodiment of the invention will be explained in greater detailhereinbelow with reference to the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic, perspective view of an electrode holder of anelectrodeposition device designed according to the invention, providedwith discharge electrodes, and

FIG. 2 is a vertical cross section through the electrode holder of FIG.1.

DESCRIPTION OF ILLUSTRATED EMBODIMENT

FIG. 1 shows an electrode holder generally designated 1. The electrodeholder 1 is made of plastic; it has four boreholes 2, by means of whichthe electrode holder can be set in place, for example, in a componentcontaining oil mist, so that the depicted electrode holder 1 can be usedto deposit oil, for example, in the crankcase ventilation of internalcombustion engines, so that the oil particles deposited can be returnedto the engine, sparing the environment.

For this purpose, three electrodes 3 are provided, being designed astwo-stage discharge electrodes. These discharge electrodes each have acorona region 4, which has a small needle-like diameter, and anelectrostatically effective region 5 with correspondingly much largerdiameter.

It is particularly evident from FIG. 2 that the electrostaticallyeffective regions 5 of the electrodes 3 are hollow in configuration.These regions of the electrodes 3 consist of an electrically conductiveplastic, and metallic needles are set into the tips of these regions 5,forming the corona regions 4 of the electrodes 3.

In all, three electrodes 3 are provided, and they are connected togetherby a curved ring-shaped line 6, and furthermore the electrodes 3 and thering line 6 are designed as a single injection-molded piece. Thecomponent of electrically conductive plastic is radially outwardlylonger than the ring-shaped line 6. In this outer region, the componentforms a contact surface 7, which serves to make contact with anelectrical feed line.

The electrode holder 1 likewise consists of plastic, but of anelectrically insulating plastic, which is cast around the electrodesubassembly. On the whole, therefore, the represented subassembly can betreated as a single piece and it allows fast installation of theelectrodeposition device. In the region of the contact surface 7, theelectrode holder 1 has a recess 8, which is configured as two steps andwhich can accommodate the electrical feed line and its insulation; theattachment of this electrical insulation to the electrode holder 1 willnot be discussed in detail here. If necessary, a detent surface can beprovided on the sleeve surrounding the recess 8, formed by the electrodeholder 1, in order to fasten the electrical insulation by means of alatching or snap-fit connection on the electrode holder 1 and ensure theelectrical contacting of the contact surface 7.

Because the overall subassembly represented consists almost entirely ofplastic (except for the needles of the corona regions 4), an especiallyvibration-resistant component is achieved, which ensures reliableoperation of the electrodeposition device even under the conditionswhich prevail in an internal combustion engine.

If necessary, the material of the electrode holder 1 can be binary indesign, in order to have both the prescribed insulating properties andthe desired shape stability. If necessary, as a departure from thesample embodiment depicted, instead of casting a single material aroundthe electrically conductive components it is possible to use a firstmaterial for the electrode holder 1, next to the electrically conductivecomponents, and to have a second material surrounding this material,forming the outer contour of the electrode holder 1.

Furthermore, as a departure from the sample embodiment depicted, theinjection-molded, electrically conductive components 3, 6, and 7 can bemade of metal instead of a conductive plastic.

An especially advantageous feature of the novel electrodeposition deviceis that the electrode holder made of plastic can also have otherfunctions, such as the holding of seals, the holding of fasteners, andthe like.

What is claimed is:
 1. An electrodeposition device, comprising two or more discharge electrodes having electrical connections including a contact area, said discharge electrodes being adapted to be connected to a common electrical feed line and to an electrically insulating electrode holder, wherein the electrode holder is made of plastic and receives the electrodes and the contact area of the electrical connections for connection to the electrical feed line.
 2. The deposition device according to claim 1, wherein the discharge electrodes are joined together to form a one-piece unit with a connecting line for electrically linking the electrodes together, said connecting line forming a contact area.
 3. The deposition device according to claim 2, wherein the electrodes are made of plastic.
 4. The deposition device according to claim 1, wherein the electrodes are made of plastic. 